>Rich said:
>
>>However, 1W carbon-comp resistors are max-rated at about 350V, so they
>>slowly change value with 1000V
>
>
>Carbon comp resistors slowly change value even when they're MIL types,
>unused, still in MIL sealed packaging. At 1000 volts, the change is rather
>faster.
>
>I'm pretty leary about using standard carbon comps for anything these days.
>..
// All of my carbon comp resistors met the trash-pickup one Monday after
I did some measurements with my Fluke DMM.
RE reading specs: It is amazing that a number of Ham amplifiers use
500pF and 1000pF 5kV doorknob caps for Tank ciruit padders which
obviously need a cap that can handle more current. The cap mfg's specs
make it clear that the 500pF and 1000pF units are intended only for
bypass and coupling service. Thus, to make a 400pF C-tune padder, 4,
100pF, 5kV units are paralled on Cu plates. The Alpha 77SX is a good
bad-example.
cheers.
- R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K,
www.vcnet.com/measures.
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